>I believe there is a study somewhere on carfree.com which contradicts the
>health issue quite clearly indicating that people in cars actually suffer
>more from car fumes.
Yes. It has been demonstrated that exhaust fumes get concentrated in a
car's interior---therefore a pedestrian standing outside the car may be
breathing in less toxic air. Not so sure about a vigorously breathing
cyclist or jogger though...
>I believe the hypothesis is that because you are
>breathing deeper and more vigorously the crud does not settle in your lungs.
...actually breathing deeper and more vigorously DOES cause more of the
crud to irritate your lungs. This was demonstrated by recent studies
linking increased asthma incidence in urban children, and even higher
incidence in urban children who participate in lots of outdoor sports.
>Anyone have the citation?
Data on air quality inside cars:
Gee I.L. and Raper D.W., 'Commuter exposure to respirable particles inside
buses and by bicycle', The Science of the Total Environment, 235, 403-405
Kingham S., Meaton J., Sheard A. and Lawrenson O., 'Assessment of exposure to
traffic-related fumes during the journey to work', Transpn Res.-D, vol 3 no
4, 271-274 (1998)
Lawryk, N. J. and Weisel, C. P., 'Concentrations of volatile organic
passenger compartments of automobiles', Environmental Science Technology
30, 810-816 (1996)
Van Wijnen, J. H., Verhoeff, A. P., Jans, H. W. A. and van Bruggen, M.,
'The exposure of cyclists, car drivers and pedestrians to traffic-related
air pollutants', International Archives of
Environmental Health 67, 187-193 (1995)
Dr Adrian Croucher
Department of Engineering Science
University of Auckland
tel 64-9-373-7599 ext 4611
A. Exclusive Official study shows that air pollution causes the
disease affecting 5m Britons
By Geoffrey Lean, Environment Editor
Pollution from car exhausts causes asthma, dramatic new official research
A massive study, backed by the Californian and US governments, has
demonstrated for the first time that ozone, the main component of smog, can
cause healthy children to develop the life-threatening condition. Top
British scientists believe it has provided the "smoking gun" that finally
links pollution to the disease.
The conclusion - which vindicates an Independent on Sunday campaign that
began more than eight years ago - is likely to have an explosive effect on
transport and health policy in Britain, which suffers from the highest
incidence of asthma in Europe.
It comes as the Government's own chief scientific adviser, Professor David
King, calls for a ban on the sale of petrol and diesel, a measure that
would drastically reduce the pollutants that cause asthma and global
warming. He says announcing a ban to take effect some years in the future
would force companies to develop "green" cars running on electricity and
More than one in every seven children in the country now suffers from
asthma - six times as many as 25 years ago - and, in all, five million
Britons have the disease: 18,000 new cases are diagnosed each week, and
1,500 people die from it every year.
Yet the Government has done little to tackle the pollution now being
identified as one of the causes of the epidemic. Ozone is excluded from
national measures being implemented by local authorities to tackle
Scientists have long agreed that ozone exacerbates the disease in those who
have it, and many have suspected that it causes it in the first place. But
in the absence of proof there has been little political interest in
tackling it. The new study breaks the impasse.
"We have known for some time that smog can trigger attacks in asthmatics,"
says Alan C Lloyd, California's top air pollution official. "This study
has shown that ozone can cause asthma as well."
Professor Rob McConnell of the University of Southern California, the
leading author of the study, and his colleagues made the connection by
mounting the first study of its kind into the disease in children. They
identified 3,535 children aged nine and over, with no history of asthma,
living in both smoggy and relatively unpolluted towns and suburbs, and
recorded what happen to them over the next five years.
Uniquely, they took particular notice of how much sport the children
played. Sporty children are exposed to more air pollution, both because
they spend more time outdoors and because vigorous exercise makes them
breathe 17 times faster, and draws air deeper into the lungs.
They found that children who played three or more sports in smoggy areas
were more than three times more likely to get asthma than equally active
children in relatively unpolluted ones. Less sporty children in polluted
towns and suburbs were also more likely to get the disease, though not to
the same extent.
Top British experts last week hailed the study as a breakthrough. "It is
very, very important - the first paper I know of that suggests that
pollution may cause asthma," said Dr John Ayres, professor of respiratory
medicine at the University of Birmingham.